Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Accurate absolute measurement of trapped Cs atoms in a MOT

M.A. Talavera

Published Jan 1, 2007• 1 citation
OpenAlex

Abstract

A Cs-133 Magneto-Optical Trap (MOT) has been developed at the Time and Frequency Division of the Centro Nacional de Metrolog´ CENAM, in Mexico. This MOT is part of a primary frequency standard based on ultra-cold Cs atoms, called CsF-1 clock, under development at CENAM. In this Cs MOT, we use the standard configuration (ae + i ae i ) 4-horizontal 2-vertical laser beams 1.9 cm in diameter, with 5 mW each. We use a 852 nm, 5 mW, DBR laser as a master laser which is stabilized by saturation spectroscopy. Emission linewidth of the master laser is 1 MHz. In order to amplify the light of the master laser, a 50 mW, 852 nm AlGaAs laser is used as slave laser. This slave laser is stabilized by light injection technique. A 12 MHz red shift of the light is performed by two double passes through two Acusto-Optic Modulators (AOMs). The optical part of the CENAMs MOT is very robust against mechanical vibration, acoustic noise and temperature changes in our laboratory, because none of our diode lasers use an extended cavity to reduce the linewidth. In this paper, we report results of our MOT characterization as a function of several operation parameters such as the intensity of laser beams, the laser beam diameter, the red shift of light, and the gradient of the magnetic field. We also report accurate absolute measurement of the number of Cs atoms trapped in our Cs MOT. We found up to6 £ 10 7 Cs atoms trapped in our MOT measured with an uncertainty no greater than 6.4%.

Related papers

Accurate absolute measurement of trapped Cs atoms in a MOT

S. Jimémez S.

A Cs-133 Magneto-Optical Trap (MOT) has been developed at the Time and Frequency Division of the Centro Nacional de Metrolog´ıa, CENAM, in Mexico. This...

Revista Mexicana de Física•Jan 1, 2007•1 citation

PROGRESS AT CENAM TOWARDS A CS FOUNTAIN CLOCK

Mauricio Lopez, Eduardo De Carlos, M. Talavera-Ortega +1 more

A primary frequency standard based on cold Cs atoms is under development at the Time and Frequency Division of the Centre Nacional de Metrologia, CENAM. A Cs magneto-optical trap has been developed using the standard sigma+sigma$4-horizontal 2-vertical laser beams of 1.9 cm in diameter, with 5 mW each. We use 852 nm, 5 mW, DBR laser as a master laser which is stabilized by saturation spectroscopy. Linewidth of the master laser is 1 MHz. A 50 mW, 852 nm, semiconductor laser is used as slave laser in order to amplify the light of the master laser. The slave laser is stabilized by injection light technique. 12 MHz red shift of the light is performed by double pass through two AOM's. In this paper we present some preliminary results of our MOT characterization as function of MOT's parameters such as intensity of laser beams and gradient of the magnetic field.

Multiconference on Electronics and Photonics (MEP)•Jan 1, 2006•1 citation

Laser cooling and trapping of Cs-133 neutral atoms at CENAM

M. Talavera-Ortega, J. M. López Romero, E. de Carlos López

At the moment the National Center of Metrology (CENAM) develops to the necessary technology for the creation of a frequency standard of high accuracy denominated CsF1 atomic fountain. The first stage of development of this clock consists of laser cooling and trapping neutral Cs-133 atoms. The mechanism of laser cooling and trapping of atoms requires of the accomplishment of a magneto-optical trap (MOT) in where is indispensable to maintain a strict control in its parameters of operation. In this experiment, the MOT operates with three set of red detuning |62s1/2, F=4|-> |62s3/2, F'=5| cyclical transition of Cs-133, mutually orthogonal, counterpropagating laser beams, with opposite circular polarization, intersecting at the center of a magnetic field which is generated by a pair of coil in anti-Helmholtz configuration. Additionally, a beam of light that comes from a repumping laser, tuned to the frequency of the |62s1/2, F=3|->|62s3/2, F'=4| transition of Cs-133, is injected to the MOT to maintain an atoms population in the |62s1/2, F=4| state. To cool and trap atoms to so low temperatures, of the order of the microkelvins on the zero absolute, by several seconds, minutes or even by several hours, provided the fundamentals tools to us to study the temporal and spatial behavior of the fluorescence of the atomic cloud and to make exact measurements in the count of such, in order to deduce the parameters of operation of the MOT that allows us to trap 1010 atoms or more. In this work the theoretical concepts as well as the experimental details of the parameters of operation of the MOT for the formation of the cold atom cloud are approached.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Feb 13, 2006•0 citations

Characterization of cold atomic cloud in a magneto-optical trap

Poonam Arora, Swatilekha Chowdhury, Ashish Agarwal +2 more

The results of characterization of cold cloud of cesium (Cs) atoms trapped in a magneto-optical trap (MOT) have been presented. The MOT is a part of the Physics package of the Cs Fountain Clock being developed at National Physical Laboratory (NPL), India. The number of atoms, size and temperature of the cloud have been measured and calculated. It is also been investigated how the number of trapped atoms changes with the trapping laser’s beam intensity, detuning and magnetic-field gradient of the trap.

•Sep 1, 2011•0 citations

Laser-cooled continuous Cs-beam master oscillator

H. Wang, Walter F. Buell, Gebriel H. Iyanu

In this paper, we present our design and prospects of a magneto-optical trap (MOT)-based cold Cs-beam atomic clock physics package and report the realization and characterization of a continuous, laser-cooled Cs atomic beam from a Cs MOT. We have determined the longitudinal velocity of the cold Cs beam by time of flight (TOF) method to be 7 m/s with a velocity spread of 1 m/s. By adjusting the MOT parameters, we are able to tune the Cs-beam velocity from 5 m/s to 8.5 m/s while the velocity spread remains to be 1 m/s. The Cs beam has an instantaneous atomic flux of 3.6 times 1010atoms/s when operated in pulsed mode and a continuous beam flux of 2 times 108atoms/s. Our theoretical simulation reveals that the MOT inhomogeneous magnetic field and the varying Doppler shift along the atomic beam propagation play an important role in determining the longitudinal velocity of the Cs atomic beam. With the cold Cs beam thus formed and a compact Ramsey cavity of 13 cm in length, we have estimated a short-term, shot-noise limited Allan standard deviation of 2.7 times 10-13pi-frac12(pi is the averaging time) for the atomic master oscillator under development

Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS)•Jan 18, 2006•2 citations

Alternative laser system for cesium magneto-optical trap via optical injection locking to sideband of a 9-GHz current-modulated diode laser

Wen-Ting Diao, Jun He, Zhi Liu +2 more

By optical injection of an 852-nm extended-cavity diode laser (master laser) to lock the + 1-order sideband of a ~9-GHz-current-modulated diode laser (slave laser), we generate a pair of phase-locked lasers with a frequency difference up to ~9-GHz for a cesium (Cs) magneto-optical trap (MOT) with convenient tuning capability. For a cesium MOT, the master laser acts as repumping laser, locked to the Cs 6S₁/₂ (F = 3) - 6P₃/₂ (F' = 4) transition. When the + 1-order sideband of the 8.9536-GHz-current-modulated slave laser is optically injection-locked, the carrier operates on the Cs 6S₁/₂ (F = 4) - 6P₃/₂ (F' = 5) cooling cycle transition with -12 MHz detuning and acts as cooling/trapping laser. When carrying a 9.1926-GHz modulation signal, this phase-locked laser system can be applied in the fields of coherent population trapping and coherent manipulation of Cs atomic ground states.

Optics Express•Mar 19, 2012•14 citations
A Cs-133 Magneto-Optical Trap (MOT) has been developed at the Time and Frequency Division of the Centro Nacional de Metrolog´ CENAM, in Mexico. This MOT is part of a primary frequency standard based on ultra-cold Cs atoms, called CsF-1 clock, under development at CENAM. In this Cs MOT, we use the standard configuration (ae + i ae i ) 4-horizontal 2-vertical laser beams 1.9 cm in diameter, with 5 mW each. We use a 852 nm, 5 mW, DBR laser as a master laser which is stabilized by saturation spectroscopy. Emission linewidth of the master laser is 1 MHz. In order to amplify the light of the master laser, a 50 mW, 852 nm AlGaAs laser is used as slave laser. This slave laser is stabilized by light injection technique. A 12 MHz red shift of the light is performed by two double passes through two Acusto-Optic Modulators (AOMs). The optical part of the CENAMs MOT is very robust against mechanical vibration, acoustic noise and temperature changes in our laboratory, because none of our diode lasers use an extended cavity to reduce the linewidth. In this paper, we report results of our MOT characterization as a function of several operation parameters such as the intensity of laser beams, the laser beam diameter, the red shift of light, and the gradient of the magnetic field. We also report accurate absolute measurement of the number of Cs atoms trapped in our Cs MOT. We found up to6 £ 10 7 Cs atoms trapped in our MOT measured with an uncertainty no greater than 6.4%.
A primary frequency standard based on cold Cs atoms is under development at the Time and Frequency Division of the Centre Nacional de Metrologia, CENAM. A Cs magneto-optical trap has been developed using the standard sigma+sigma$4-horizontal 2-vertical laser beams of 1.9 cm in diameter, with 5 mW each. We use 852 nm, 5 mW, DBR laser as a master laser which is stabilized by saturation spectroscopy. Linewidth of the master laser is 1 MHz. A 50 mW, 852 nm, semiconductor laser is used as slave laser in order to amplify the light of the master laser. The slave laser is stabilized by injection light technique. 12 MHz red shift of the light is performed by double pass through two AOM's. In this paper we present some preliminary results of our MOT characterization as function of MOT's parameters such as intensity of laser beams and gradient of the magnetic field.
At the moment the National Center of Metrology (CENAM) develops to the necessary technology for the creation of a frequency standard of high accuracy denominated CsF1 atomic fountain. The first stage of development of this clock consists of laser cooling and trapping neutral Cs-133 atoms. The mechanism of laser cooling and trapping of atoms requires of the accomplishment of a magneto-optical trap (MOT) in where is indispensable to maintain a strict control in its parameters of operation. In this experiment, the MOT operates with three set of red detuning |62s1/2, F=4|-> |62s3/2, F'=5| cyclical transition of Cs-133, mutually orthogonal, counterpropagating laser beams, with opposite circular polarization, intersecting at the center of a magnetic field which is generated by a pair of coil in anti-Helmholtz configuration. Additionally, a beam of light that comes from a repumping laser, tuned to the frequency of the |62s1/2, F=3|->|62s3/2, F'=4| transition of Cs-133, is injected to the MOT to maintain an atoms population in the |62s1/2, F=4| state. To cool and trap atoms to so low temperatures, of the order of the microkelvins on the zero absolute, by several seconds, minutes or even by several hours, provided the fundamentals tools to us to study the temporal and spatial behavior of the fluorescence of the atomic cloud and to make exact measurements in the count of such, in order to deduce the parameters of operation of the MOT that allows us to trap 1010 atoms or more. In this work the theoretical concepts as well as the experimental details of the parameters of operation of the MOT for the formation of the cold atom cloud are approached.
The results of characterization of cold cloud of cesium (Cs) atoms trapped in a magneto-optical trap (MOT) have been presented. The MOT is a part of the Physics package of the Cs Fountain Clock being developed at National Physical Laboratory (NPL), India. The number of atoms, size and temperature of the cloud have been measured and calculated. It is also been investigated how the number of trapped atoms changes with the trapping laser’s beam intensity, detuning and magnetic-field gradient of the trap.
In this paper, we present our design and prospects of a magneto-optical trap (MOT)-based cold Cs-beam atomic clock physics package and report the realization and characterization of a continuous, laser-cooled Cs atomic beam from a Cs MOT. We have determined the longitudinal velocity of the cold Cs beam by time of flight (TOF) method to be 7 m/s with a velocity spread of 1 m/s. By adjusting the MOT parameters, we are able to tune the Cs-beam velocity from 5 m/s to 8.5 m/s while the velocity spread remains to be 1 m/s. The Cs beam has an instantaneous atomic flux of 3.6 times 1010atoms/s when operated in pulsed mode and a continuous beam flux of 2 times 108atoms/s. Our theoretical simulation reveals that the MOT inhomogeneous magnetic field and the varying Doppler shift along the atomic beam propagation play an important role in determining the longitudinal velocity of the Cs atomic beam. With the cold Cs beam thus formed and a compact Ramsey cavity of 13 cm in length, we have estimated a short-term, shot-noise limited Allan standard deviation of 2.7 times 10-13pi-frac12(pi is the averaging time) for the atomic master oscillator under development
By optical injection of an 852-nm extended-cavity diode laser (master laser) to lock the + 1-order sideband of a ~9-GHz-current-modulated diode laser (slave laser), we generate a pair of phase-locked lasers with a frequency difference up to ~9-GHz for a cesium (Cs) magneto-optical trap (MOT) with convenient tuning capability. For a cesium MOT, the master laser acts as repumping laser, locked to the Cs 6S₁/₂ (F = 3) - 6P₃/₂ (F' = 4) transition. When the + 1-order sideband of the 8.9536-GHz-current-modulated slave laser is optically injection-locked, the carrier operates on the Cs 6S₁/₂ (F = 4) - 6P₃/₂ (F' = 5) cooling cycle transition with -12 MHz detuning and acts as cooling/trapping laser. When carrying a 9.1926-GHz modulation signal, this phase-locked laser system can be applied in the fields of coherent population trapping and coherent manipulation of Cs atomic ground states.